A．Some of their prisoners are allowed to study or work outside prisons.
B．Most of their prisoners are expected to work.
C．Their prisoners are often sent to special centers for skill training.
D．Their prisoners are allowed freedom to visit their families.

A．The first period of cold, wintry days in autumn.
B．The turning of color and falling of leaves.
C．A large mass of warm tropical air carried northward.
D．The southwestern winds.